糖的吡喃式可以重排成呋喃式，然后保护： CH>OH Hc-&-cH H3C 1.NaOH HO (CH3O)2S02 2.HCI,H2O CH3 Organic Chem Organic Chem 糖的吡喃式可以重排成呋喃式，然后保护： O H HO H HO H OH H OH OH O C H HO H H OH OH H CH2OH HO H H3C C O CH3 O C H HO H H O O H CH2 O H O H3C H3C CH3 H3C 1. NaOH (CH3O) 2 SO2 2. HCl ,H2O O H HO H H3CO H OH H OH OH